Reuse

Abstract

Building a testbench—designing, coding, debugging, and testing drivers, monitors, and other testbench components—can be quite time-consuming. An obvious place to improve verification productivity is to reuse components. That sounds simple enough, but to make a component truly reusable, some thought must be put into its architecture and construction. The types of things to think about to make a component reusable include how you expect to reuse the component and what degree of freedom the component must support.

The essential means to make a component reusable is to encapsulate all the data and functionality behind a well-defined interface. The interface dictates how you can modify, operate, and interrogate (extract data from) the component. All access is prohibited except that specifically allowed by the interface. We’ll consider four techniques for building reusable testbench elements: function calls, parameterized classes, inheritance, and configuration. Each of these techniques represents a different way of modifying structure or behavior using an interface. In each of these techniques, information is supplied externally to change the structure or behavior of the element. The first three ways to make an element reusable are a recap from Chapter 2, where we discussed object-oriented programming.